Archive for the ‘water’ Category

Lakes worldwide feel the heat from climate change, Warming waters are disrupting freshwater fishing and recreation, Science News ,BY ALEXANDRA WITZE MAY 1, 2017 “……..When most people think of the physical effects of climate change, they picture melting glaciers, shrinking sea ice or flooded coastal towns (SN: 4/16/16, p. 22). But observations like those at Stannard Rock are vaulting lakes into the vanguard of climate science. Year after year, lakes reflect the long-term changes of their environment in their physics, chemistry and biology. “They’re sentinels,” says John Lenters, a limnologist at the University of Wisconsin–Madison.

Globally, observations show that many lakes are heating up — but not all in the same way or with the same ecological consequences. In eastern Africa, Lake Tanganyika is warming relatively slowly, but its fish populations are plummeting, leaving people with less to eat. In the U.S. Upper Midwest, quicker-warming lakes are experiencing shifts in the relative abundance of fish species that support a billion-dollar-plus recreational industry. And at high global latitudes, cold lakes normally covered by ice in the winter are seeing less ice year after year — a change that could affect all parts of the food web, from algae to freshwater seals.

Understanding such changes is crucial for humans to adapt to the changes that are likely to come, limnologists say. Indeed, some northern lakes will probably release more methane into the air as temperatures rise — exacerbating the climate shift that is already under way.

Lake layers

Lakes and ponds cover about 4 percent of the land surface not already covered by glaciers. That may sound like a small fraction, but lakes play a key role in several planetary processes. Lakes cycle carbon between the water’s surface and the atmosphere. They give off heat-trapping gases such as
carbon dioxide and methane, while simultaneously tucking away carbon in decaying layers of organic muck at lake bottoms. They bury nearly half as much carbon as the oceans do.

Yet the world’s more than 100 million lakes are often overlooked in climate simulations. That’s surprising, because lakes are far easier to measure than oceans. Because lakes are relatively small, scientists can go out in boats or set out buoys to survey temperature, salinity and other factors at different depths and in different seasons.

A landmark study published in 2015 aimed to synthesize these in-water measurements with satellite observations for 235 lakes worldwide. In theory, lake warming is a simple process: The hotter the air above a lake, the hotter the waters get. But the picture is far more complicated than that, the international team of researchers found.

Globally, observations show that many lakes are heating up — but not all in the same way or with the same ecological consequences. In eastern Africa, Lake Tanganyika is warming relatively slowly, but its fish populations are plummeting, leaving people with less to eat. In the U.S. Upper Midwest, quicker-warming lakes are experiencing shifts in the relative abundance of fish species that support a billion-dollar-plus recreational industry. And at high global latitudes, cold lakes normally covered by ice in the winter are seeing less ice year after year — a change that could affect all parts of the food web, from algae to freshwater seals.

Understanding such changes is crucial for humans to adapt to the changes that are likely to come, limnologists say. Indeed, some northern lakes will probably release more methane into the air as temperatures rise — exacerbating the climate shift that is already under way.

Lake layers

Lakes and ponds cover about 4 percent of the land surface not already covered by glaciers. That may sound like a small fraction, but lakes play a key role in several planetary processes. Lakes cycle carbon between the water’s surface and the atmosphere. They give off heat-trapping gases such as
carbon dioxide and methane, while simultaneously tucking away carbon in decaying layers of organic muck at lake bottoms. They bury nearly half as much carbon as the oceans do.

Yet the world’s more than 100 million lakes are often overlooked in climate simulations. That’s surprising, because lakes are far easier to measure than oceans. Because lakes are relatively small, scientists can go out in boats or set out buoys to survey temperature, salinity and other factors at different depths and in different seasons.

A landmark study published in 2015 aimed to synthesize these in-water measurements with satellite observations for 235 lakes worldwide. In theory, lake warming is a simple process: The hotter the air above a lake, the hotter the waters get. But the picture is far more complicated than that, the international team of researchers found.

On average, the 235 lakes in the study warmed at a rate of 0.34 degrees Celsius per decade between 1985 and 2009. Some warmed much faster, like Finland’s Lake Lappajärvi, which soared nearly 0.9 degrees each decade. A few even cooled, such as Blue Cypress Lake in Florida. Puzzlingly, there was no clear trend in which lakes warmed and which cooled. The most rapidly warming lakes were scattered across different latitudes and elevations.

Even some that were nearly side by side warmed at different rates from one another — Lake Superior, by far the largest of the Great Lakes, is warming much more rapidly, at a full degree per decade, than others in the chain, although Huron and Michigan are also warming fast.

“Even though lakes are experiencing the same weather, they are responding in different ways,” says Stephanie Hampton, an aquatic biologist at Washington State University in Pullman.

Such variability makes it hard to pin down what to expect in the future. But researchers are starting to explore factors such as lake depth and lake size (intuitively, it’s less teeth-chattering to swim in a small pond in early summer than a big lake).

Fracking kills newborn babies – polluted water likely cause http://www.theecologist.org/News/news_round_up/2988876/fracking_kills_newborn_babies_polluted_water_likely_cause.html, Oliver Tickell, 25th April 2017 A new study in Pennsylvania, USA shows that fracking is strongly related to increased mortality in young babies. The effect is most pronounced in counties with many drinking water wells indicating that contamination by ‘produced water’ from fracking is a likely cause. Radioactive pollution with uranium, thorium and radium is a ‘plausible explanation’ for the excess deaths.

A new study of Pennsylvania counties published today in the Journal of Environmental Protection shows for the first time that contamination from fracking kills babies.

The Marcellus shale area of Pennsylvania was one of the first regions where novel gas drilling involving hydraulic fracturing of sub-surface rock, now termed ‘fracking’, was carried out.

The epidemiological study by Christopher Busby and Joseph Mangano examines early infant deaths 0-28 days before and after the drilling of fracking wells, using official data from the US Centre for Disease Control to compare the immediate post-fracking four year period 2007-2010 with the pre-fracking four-year period 2003-2006.

Results showed a statistically significant 29% excess risk of dying age 0-28 days in the ten heavily fracked counties of Pennsylvania during the four-year period following the development of fracking gas wells. Over the same period, the State rate declined by 2%. They conclude:

“There were about 50 more babies died in these 10 counties than would have been predicted if the rate had been the same over the period as all of Pennsylvania, where the incidence rate fell over the same period.”

Radioactive water pollution to blame?

The Marcellus shale beneath Pennsylvania was one of the first areas where fracking began. Only 44 fracking wells were drilled before 2007, while 2,864 were drilled in 2007-2010.

The cause of the excess mortality is not proven in the study, however the authors point out that the fracking production process releases naturally occurring radioactive materials from shale strata which then contaminate groundwater.

These include radium, uranium, thorium and radon, an intensely radioactive gas which decays into radioactive ‘daughters’ with a half life of under four days. And as the authors write, fracking “involves the explosive destruction of large volumes of underground gas and oil retaining rocks and the pumping down of large amounts of what is termed ‘produced water’ which initially contains various chemical and sand additives.

“This produced water and backflow returns to the surface with a high load of dissolved and suspended solids including naturally occurring radioactive elements … The contaminated water has to be safely disposed of but this is often associated with violations of legal disposal constraints.”

Baby mortality related to exposure through water wells

In the five heavily-fracked counties in the northeast part of the state (Susquehanna, Bradford, Wyoming, Lycoming and Tioga), the number of deaths from 2003-2006 vs. 2007-2010 climbed from 36 to 60, a statistically significant rate increase of 66%.

The rate in the five counties in southwest Pennsylvania (Washington, Westmoreland, Greene, Butler and Fayette) rose 18%, from 157 to 178 deaths, though this increase was not statistically significant.

This divergence in relative risk between the heavily fracked NE and SW counties was initially perplexing, however the authors noticed the higher dependence on private water wells (potentially contaminated with frackiing fluids) for drinking water and other needs in the first region compared to the second.

In the NE group of counties , the number of water wells per birth ranged from 4.9 to 13.5, compared to 1.1 to 3 in the SW group of countries. Their chart of Relative Risk for early infant mortality after fracking (see image above right) plotted against ‘exposure’ defined as ‘water wells per birth’ on a county by county basis produced a straight-line graph – indicated a strong relation to increased mortality and exposure to groundwater.

They conclude: “The results therefore seem to support the suggestion that the vector for the effect is exposure to drinking water from private wells. This is a mechanistically plausible explanation. However the findings do not prove such a suggestion. We may examine other possible explanations for possible health effects which have been advanced.”

While radioactive pollution is carefully examined, the authors acknowledge alternatives including “the existence of chemical contaminants in the produced water” which they consider a “possible but unknown factor.”

Serious questions raised over health hazards of fracking

“A major component of early infant mortality is congenital malformation, e.g., heart, neurological, and kidney defects. These are known to be caused by exposures to Radium and Uranium in drinking water”, said Christopher Busby.

“Infant death rates were significantly high in highly-fracked counties in northeast Pennsylvania, those with the greatest density of private water wells, suggesting it is drinking water contamination driving the effect.”

Joseph Mangano added: “These results raise serious questions about potential health hazards of fracking, especially since the fetus and infant are most susceptible to environmental pollutants. This is a public health issue which should be investigated wherever fracking is being carried out or proposed.”

The result is expected to have significant insurance, investment, economic and downstream political implications in the US and other countries.

Dr Busby is the Scientific Secretary of the European Committee on Radiation Risk www.ecrr.eu and is Scientific Director of Environmental Research SIA, based in the Latvian National Academy of Sciences, Riga, Latvia. Busby’s CV can be found here.

A recent study helps describe how uranium cycles through the environment at former uranium mining sites and why it can be difficult to remove.

Decades after a uranium mine is shuttered, the radioactive element can still persist in groundwater at the site, despite cleanup efforts.

A recent study led by scientists at the Department of Energy’s SLAC National Accelerator Laboratory helps describe how the contaminant cycles through the environment at former uranium mining sites and why it can be difficult to remove. Contrary to assumptions that have been used for modeling uranium behavior, researchers found the contaminant binds to organic matter in sediments. The findings provide more accurate information for monitoring and remediation at the sites.

The results were published in the Proceedings of the National Academy of Sciences.

In 2014, researchers at SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL) began collaborating with the DOE Office of Legacy Management, which handles contaminated sites associated with the legacy of DOE’s nuclear energy and weapons production activities. Through projects associated with the Uranium Mill Tailings Radiation Control Act, the DOE remediated 22 sites in Colorado, Wyoming and New Mexico where uranium had been extracted and processed during the 1940s to 1970s.

Uranium was removed from the sites as part of the cleanup process, and the former mines and waste piles were capped more than two decades ago. Remaining uranium deep in the subsurface under the capped waste piles was expected to leave these sites due to natural groundwater flow. However, uranium has persisted at elevated levels in nearby groundwater much longer than predicted by scientific modeling………

“For the most part, uranium contamination has only been looked at in very simple model systems in laboratories,” Bone says. “One big advancement is that we are now looking at uranium in its native environmental form in sediments. These dynamics are complicated, and this research will allow us to make field-relevant modeling predictions.”In an earlier study, the SLAC team discovered that uranium accumulates in the low-oxygen sediments near one of the waste sites in the upper Colorado River basin. These deposits contain high levels of organic matter — such as plant debris and bacterial communities.During this latest study, the researchers found the dominant form of uranium in the sediments, known as tetravalent uranium, binds to organic matter and clays in the sediments. This makes it more likely to persist at the sites. The result conflicted with current models used to predict movement and longevity of uranium in sediments, which assumed that it formed an insoluble mineral called uraninite.

Different chemical forms of the element vary widely in how mobile they are — how readily they move around — in water, says Sharon Bone, lead author on the paper and a postdoctoral researcher at SSRL, a DOE Office of Science User Facility.

Since the uranium is bound to organic matter in sediments, it is immobile under certain conditions. Tetravalent uranium may become mobile when the water table drops and oxygen from the air enters spaces in the sediment that were formerly filled with water, particularly if the uranium is bound to organic matter in sediments rather than being stored in insoluble minerals.

“Either you want the uranium to be soluble and completely flushed out by the groundwater, or you just want the uranium to remain in the sediments and stay out of the groundwater,” Bone says. “But under fluctuating seasonal conditions, neither happens completely.”

This cycling in the aquifer may result in the persistent plumes of uranium contamination found in groundwater, something that wasn’t captured by earlier modeling efforts.

— In the last days of the Obama Administration, the U.S. Environmental Protection Agency is about to dramatically increase allowable public exposure to radioactivity to levels thousands of times above the maximum limits of the Safe Drinking Water Act, according to documents the agency surrendered in a federal lawsuit brought by Public Employees for Environmental Responsibility (PEER). These radical rollbacks cover the “intermediate period” following a radiation release and could last for up to several years. This plan is in its final stage of approval.

The documents indicate that the plan’s rationale is rooted in public relations, not public health. Following Japan’s Fukushima meltdown in 2011, EPA’s claims that no radioactivity could reach the U.S. at levels of concern were contradicted by its own rainwater measurements showing contamination from Fukushima throughout the U.S. well above Safe Drinking Water Act limits. In reaction, EPA prepared new limits 1000s of times higher than even the Fukushima rainwater because “EPA experienced major difficulties conveying to the public that the detected levels…were not of immediate concern for public health.”

When EPA published for public comment the proposed “Protective Action Guides,” it hid proposed new concentrations for all but four of the 110 radionuclides covered, and refused to reveal how much they were above Safe Drinking Water Act limits. It took a lawsuit to get EPA to release documents showing that –

The proposed PAGs for two radionuclides (Cobalt-60 and Calcium-45) are more than 10,000 times Safe Drinking Water Act limits. Others are hundreds or thousands of times higher;

According to EPA’s own internal analysis, some concentrations are high enough to deliver a lifetime permissible dose in a single day. Scores of other radionuclides would be allowed at levels that would produce a lifetime dose in a week or a month;

The levels proposed by the Obama EPA are higher than what the Bush EPA tried to adopt–also in its final days. That plan was ultimately withdrawn; and

EPA hid the proposed increases from the public so as to “avoid confusion,” intending to release the higher concentrations only after the proposal was adopted. The documents also reveal that EPA’s radiation division even hid the new concentrations from other divisions of EPA that were critical of the proposal, requiring repeated efforts to get them to even be disclosed internally.

“To cover its embarrassment after being caught dissembling about Fukushima fallout on American soil, EPA is pursuing a justification for assuming a radioactive fetal position even in cases of ultra-high contamination,” stated PEER Executive Director Jeff Ruch, noting that New York Attorney General Eric Schneiderman has called for the PAGs to be withdrawn on both public health and legal grounds. “The Safe Drinking Water Act is a federal law; it cannot be nullified or neutered by regulatory ‘guidance.’”Despite claims of transparency, EPA solicited public comment on its plan even as it hid the bulk of the plan’s effects. Nonetheless, more than 60,000 people filed comments in opposition.

“The Dr. Strangelove wing of EPA does not want this information shared with many of its own experts, let alone the public,” added Ruch, noting that PEER had to file a Freedom of Information Act lawsuit to force release of exposure limits. “This is a matter of public health that should be promulgated in broad daylight rather than slimed through in the witching hours of a departing administration.”

A new study has determined the impact of intrinsic colloid formation on increased migration of leaked radioactive materials in the environment. Colloids are microscopic inorganic or organic solids that remain suspended in water. Intrinsic colloids are formed when radioactive waste mixes with other dissolved components in the groundwater, such as bicarbonate.

Researchers at Ben-Gurion University of the Negev (BGU) have found that radioactive matter migrates more quickly in carbonate bedrock formations once it has leaked from a tank from near surface waste sites and geological repositories.

Corroded stored waste containers can lead to radionuclide (radioactive) leakage, which may reach groundwater.

The study, published in the online journal Environmental Science & Technology (ACS Publications), determined the impact of intrinsic colloid formation on increased migration of leaked radioactive materials in the environment. Colloids are microscopic inorganic or organic solids that remain suspended in water. Intrinsic colloids are formed when radioactive waste mixes with other dissolved components in the groundwater, such as bicarbonate.

“This study showed that intrinsic colloids formed by interactions between soluble Cerium (Ce) and carbonates significantly increase the mobility of Ce injected into a carbonate rock fracture,” explains BGU Zuckerberg Institute for Water Research Director Prof. Noam Weisbrod, Ph.D. “The formation of intrinsic colloids, if not accounted for, could result in the under prediction of radionuclide migration through fractures in fine-grained carbonate bedrock, such as chalk.”……..http://www.sciencedaily.com/releases/2015/12/151218110259.htm

Groundwater a significant issue: nuclear royal commission, IN Daily,
Adelaide Indpendent News, 30 April PETER GILL | 30 APRIL 2015 The potential impact of a nuclear waste storage facility on South Australia’s groundwater systems is one of the “significant issues” that need to be addressed in any consideration of expanding the nuclear fuel cycle, according to the royal commission.The second issues paper published by the royal commission says the siting and operation of a waste storage or disposal facility must take potential environmental impacts into account.

“Site selection for a storage or disposal facility would consider the type of facility and waste being stored (including its longevity), geological stability, generation of heat, geographical matters as well as operational issues such as amenity,” the paper says.“In addition to the management of radiative exposure, a significant issue is the potential for the contamination of groundwater sources.

“Addressing that issue requires an understanding of the current frequency, flow and volume of surface and ground waters. “Management of water resources from sourcing and storage will be required if such a facility were to be sited in South Australia.

“Also significant is the potential risk of land contamination at handling, storage and disposal sites.

“Aside from its ecological impact upon animals and plants, contamination of the environment has implications for the health and safety of humans who use those resources.”

Rollback in Nuclear Radiation Cleanup By Global Research News, September 19, 2014 by Public Employees for Environmental Responsibility (PEER)

The White House has given final approval for dramatically raising permissible radioactive levels in drinking water and soil following “radiological incidents,” such as nuclear power-plant accidents and dirty bombs. The final version, slated for Federal Register publication as soon as today, is a win for the nuclear industry which seeks what its proponents call a “new normal” for radiation exposure among the U.S population, according Public Employees for Environmental Responsibility (PEER).

Issued by the Environmental Protection Agency, the radiation guides (called Protective Action Guides or PAGs) allow cleanup many times more lax than anything EPA has ever before accepted. These guides govern evacuations, shelter-in-place orders, food restrictions and other actions following a wide range of “radiological emergencies.” The Obama administration blocked a version of these PAGs from going into effect during its first days in office. The version given approval late last Friday is substantially similar to those proposed under Bush but duck some of the most controversial aspects:

In soil, the PAGs allow long-term public exposure to radiation in amounts as high as 2,000 millirems. This would, in effect, increase a longstanding 1 in 10,000 person cancer rate to a rate of 1 in 23 persons exposed over a 30-year period;

In water, the PAGs punt on an exact new standard and EPA “continues to seek input on this.” But the thrust of the PAGs is to give on-site authorities much greater “flexibility” in setting aside established limits; and

Resolves an internal fight inside EPA between nuclear versus public health specialists in favor of the former. The PAGs are the product of Gina McCarthy, the assistant administrator for air and radiation whose nomination to serve as EPA Administrator is taken up this week by the Senate.

Despite the years-long internal fight, this is the first public official display of these guides. This takes place as Japan grapples with these same issues in the two years following its Fukushima nuclear disaster.

“This is a public health policy only Dr. Strangelove could embrace. If this typifies the environmental leadership we can expect from Ms. McCarthy, then EPA is in for a long, dirty slog,” stated PEER Executive Director Jeff Ruch, noting that the EPA package lacks a cogent rationale, is largely impenetrable and hinges on a series of euphemistic “weasel words.”

“No compelling justification is offered for increasing the cancer deaths of Americans innocently exposed to corporate miscalculations several hundred-fold.”

Reportedly, the PAGs had been approved last fall but their publication was held until after the presidential election. The rationale for timing their release right before McCarthy’s confirmation hearing is unclear.

Since the PAGs guide agency decision-making and do not formally set standards or repeal statutory requirements, such as the Safe Drinking Water Act and Superfund, they will go into full effect following a short public comment period. Nonetheless, the PAGs will likely determine what actions take place on the ground in the days, weeks, months and, in some cases, years following a radiological emergency.

Scientists studying the effects of ISL doubt how quickly mine sites can self-cleanse. This uncertainty appears to be little known to both Kazakhstan’s nuclear industry and fledgling environmentalists.

no site in the US has been entirely returned to pre-mining conditions

The cost of being the world’s No.1 uranium producer Kazakhstan’s industry has skyrocketed in the past 10 years. But what could that mean for the environment? Christian Science Monitor, By Ben Arnoldy, Staff writer / August 28, 2013 ASTANA, KAZAKHSTAN

If you make a toxic mess under one of the most isolated parts of the planet, does it matter if you don’t clean it up? Does it make a difference if that mess will be there for thousands of years? Scientists are asking those questions as Kazakhstan has steadily risen to become the world’s No. 1 uranium producer, surpassing such nations as the United States, Canada, and Australia, which require more cleanup.

Rather than employing miners to haul rock up to the surface, mine operators in Kazakhstan have embraced a newer – and generally cleaner – process by which a chemical solution is injected down a pipe to dissolve the underground uranium deposits and then is sucked back up to the surface.

This in situ leach (ISL) method avoids making a mess above ground, but leaves toxic levels of heavy metals in the ground water. In the US, companies using the method have tried for years and failed to return ground water to its pre-mining state.

Scientists studying the effects of ISL doubt how quickly mine sites can self-cleanse. This uncertainty appears to be little known to both Kazakhstan’s nuclear industry and fledgling environmentalists.

In the near term, the stakes do not appear high: Kazakhstan’s uranium mines are mostly located in deserted areas of an already sparsely populated country. But as the US learned in its own uranium-rich Southwest, population patterns and land use can change, potentially deferring an expensive cleanup or rendering some water resources unusable.

“Kazakhstan is a growing country and the pollution could persist for up to thousands of years, and you just don’t know in the future if people might live in the area,” says Brian Reinsch, an environmental scientist researching ISL remediation methods in Kazakhstan…….

Drinking water

ISL mining in many parts of the world involves some treatment of the solution that is left behind in the ore-bearing aquifers. If untreated, the solution could contain arsenic and cadmium at levels thousands of times higher than drinking water standards, says Gavin Mudd, an environmental engineer at Monash University in Australia. Arsenic can also be absorbed by plants, leaving the water unusable for irrigating crops.

Over time, the contaminated water will gradually spread laterally – often at paces as slow as a meter per year – beyond the mining site. ISL mine sites are chosen in areas where there are barriers like clay above and below the ore deposit to prevent water from seeping vertically into new aquifers with higher quality water.

But the clay layer is not entirely continuous, nor is it certain the mining acid wouldn’t dissolve the clay, according to Reinsch. Furthermore, the mining process treats the ore-bearing aquifer like a pincushion, drilling holes all over the area. These are plugged up. But there is uncertainty about the spread of contamination over the long haul.

“Even if we were monitoring for five or 10 years, that’s nowhere near enough. We need literally hundreds of years of data of watching these sites to show yes, they are stable,” says Dr. Mudd…….

The turbine buildings at the Fukushima Dai-ichi plant are about 150 meters (500 feet) from the ocean. According to a Japan Atomic Energy Agency document, the contaminated underground water is spreading toward the sea at a rate of about 4 meters (13 feet) a month.

At that rate, “the water from that area is just about to reach the coast,” if it hasn’t already,

radioactive cesium levels in most fish caught off the Fukushima coast hadn’t declined in the year following the March 2011 disaster, suggesting that the contaminated water from the reactor-turbine areas is already leaking into the sea.

But TEPCO hasn’t provided the details he and other scientists need to further assess the situation.

Radioactive Groundwater at Fukushima Nears Pacific abc news, TOKYO August 23, 2013 (AP) By MARI YAMAGUCHI Associated Press Deep beneath Fukushima’s crippled nuclear power station, a massive underground reservoir of contaminated water that began spilling from the plant’s reactors after the 2011 earthquake and tsunami has been creeping slowly toward the Pacific.

Now, 2 1/2 years later, experts fear it is about to reach the ocean and greatly worsen what is fast becoming a new crisis at Fukushima: the inability to contain vast quantities of radioactive water.

The looming crisis is potentially far greater than the discovery earlier this week of a leak from a tank that stores contaminated water used to cool the reactor cores. That 300-ton (80,000-gallon) leak is the fifth and most serious from a tank since the March 2011 disaster, when three of the plant’s reactors melted down after a huge earthquake and tsunami knocked out the plant’s power and cooling functions.

But experts believe the underground seepage from the reactor and turbine building area is much bigger and possibly more radioactive, confronting the plant’s operator, Tokyo Electric Power Co., with an invisible, chronic problem and few viable solutions. Many also believe it is another example of how TEPCO has repeatedly failed to acknowledge problems that it could almost certainly have foreseen — and taken action to mitigate before they got out of control.

It remains unclear what the impact of the contamination on the environment will be because the radioactivity will be diluted as it spreads farther into the sea. Most fishing in the area is already banned, but fishermen in nearby Iwaki City had been hoping to resume test catches next month following favorable sampling results. Those plans have been scrapped after news of the latest tank leak.

“Nobody knows when this is going to end,” said Masakazu Yabuki, a veteran fisherman in Iwaki, just south of the plant, where scientists say contaminants are carried by the current. “We’ve suspected (leaks into the ocean) from the beginning. … TEPCO is making it very difficult for us to trust them.”

To keep the melted nuclear fuel from overheating, TEPCO has rigged a makeshift system of pipes and hoses to funnel water into the broken reactors. The radioactive water is then treated and stored in the aboveground tanks that have now developed leaks. But far more leaks into the reactor basements during the cooling process — then through cracks into the surrounding earth and groundwater.

About 1,000 tons of underground water from the mountains flows into the plant compound each day, of which 400 tons seep into the reactor and turbine basements and get contaminated. The remaining 600 avoids that area, but at least half of it is believed to eventually come in contact with contamination elsewhere before entering the sea, according to an estimate by Japan’s Agency for Natural Resources and Energy.

Scientists, pointing to stubbornly high radioactive cesium levels in bottom-dwelling fish since the disaster, had for some time suspected the plant was leaking radioactive water into the ocean. TEPCO repeatedly denied that until last month, when it acknowledged contaminated water has been leaking into the ocean from early in the crisis. Even so, the company insists the seepage is coming from part of a network of maintenance tunnels, called trenches, near the coast, rather than underground water coming out of the reactor and turbine area.

So far, we don’t have convincing data that confirm a leak from the turbine buildings. But we are open to consider any possible path of contamination,” said TEPCO spokesman Yoshimi Hitosugi.

The turbine buildings at the Fukushima Dai-ichi plant are about 150 meters (500 feet) from the ocean. According to a Japan Atomic Energy Agency document, the contaminated underground water is spreading toward the sea at a rate of about 4 meters (13 feet) a month.

At that rate, “the water from that area is just about to reach the coast,” if it hasn’t already, said Atsunao Marui, an underground water expert at the National Institute of Advanced Industrial Science and Technology who is on a government committee studying the contaminated water problem. “We must contain the problem as quickly as possible.”…..

Leaks of highly contaminated water from the aboveground tanks aggravate the groundwater problem.

“Any contamination in the groundwater would eventually flow into the ocean. That is very difficult to stop even with barriers,” said Ken Buesseler, a marine chemist at the Woods Hole Oceanographic Institution in Massachusetts. He found that radioactive cesium levels in most fish caught off the Fukushima coast hadn’t declined in the year following the March 2011 disaster, suggesting that the contaminated water from the reactor-turbine areas is already leaking into the sea.

“……..Toxic Sludge. Tepco was storing 330,000 tons of radioactive water as of Aug. 13 in tanks covering an area equal to 37 football fields, according to the company. The utility is clearing forest to make room for more tanks as it adds to the stored water at a rate of 400 tons a day after pumping it out from under the plant’s reactors, which melted down as a result of the March 2011 earthquake and tsunami.

The water is treated to remove some of the cesium particles before it is stored, which has left 480 filters clogged with the radioactive material at the site. Each weigh 15 tons and are warehoused in what the utility calls temporary storage, though it will take hundreds of years for the radiation to decay. Other radioactive contaminants remain in the water even after treatment. That includes strontium, which has been linked to bone cancers.

Besides radiated water, the site north of Tokyo has more than 73,000 cubic meters of contaminated concrete, 58,000 cubic meters of irradiated trees and undergrowth, and 157,710 gallons of toxic sludge, according to the utility.

’Biggest Concern’

Japan’s nuclear watchdog has ratcheted up alarm over the potential for more leaks of highly radioactive water from the hundreds of storage tanks at the Fukushima atomic plant.

The possibility of leaks from other tanks “is the biggest concern,” said Nuclear Regulation Authority Chairman Shunichi Tanaka at a press conference yesterday. “This will need to be handled carefully on the assumption that one incident could bring another.”

Late last night, Tepco said water leaking from the storage tank probably ran into the ocean, citing high radiation readings in a drainage ditch.

As much as 20 trillion becquerels of cesium and 10 trillion becquerels of strontium leaked into the ocean since May 2011, Tepco spokeswoman Mayumi Yoshida said today. The total amount of cesium and strontium is equivalent to about 100 times the annual limit on radiation from the plant to the ocean under normal conditions, according to calculations based on Tepco data……….

Leaking Tanks

Japan’s government has ordered an investigation into the safety of hundreds of other tanks storing contaminated water in Fukushima, the site of the world’s worst civilian nuclear disaster since the Chernobyl reactor exploded in 1986.